1. Field of the Invention
The present invention relates to an image processing apparatus, a method for controlling the image processing apparatus, a program, and a storage medium. More specifically, the present invention relates to user authentication performed in an image processing apparatus providing at least one service.
2. Description of the Related Art
In recent years, various operations and high-value-added expanded functions as well as a conventional standalone function have been realized by computers (personal computers (PCs)), peripheral devices, and multifunction printers (MFPs) connected through a network. In this environment, network printing, transmission of scan images through a network, and account management in copying or printing are managed in centralized management by a master PC through a network. Further, by appropriately authenticating/identifying each user and authorizing the user to use an apparatus based on user authority under centralized management, the MFP or the like can be protected against unauthorized users.
By connecting an MFP and PC to a network, the function of the MFP, that has conventionally functioned on a standalone basis and whose ability has been limited, can be enhanced. On the other hand, in such a situation that the MFP is remotely available through a network from a physically remote place, problems of leakage of information or unauthorized use of the MFP tend to increase. Accordingly, a user authentication function or an access control function has been provided in MFPs in order to overcome these problems.
Typically, the MFP has been provided with a simple security function since the MFP was used on a standalone basis. However, due to the above-described background, MFPs having a safer and reinforced security function have been developed. At the same time, this reinforced high-security function itself has been regarded as added value of MFPs, and has been separately sold as an optional product which is to be installed into the MFP.
In an MFP having a reinforced security function, a user login function or an access control function can be used to prevent leakage of confidential information. When an MFP having such a reinforced security function is used, a login screen is displayed on a display of an operation panel. Before using the MFP, a user has to input a user ID and a password to pass user authentication in order to access the operation screen of the MFP.
Once the user passed the user authentication, an operation screen is displayed on the operation panel of the MFP, so that the user can use functions of copy, FAX, scan, and transmission of an electronic file. After the user ends the operation of the MFP, the user explicitly presses a logout button to perform logout. Under a login state, the user can freely specify any operation. Even if the user goes away from the MFP without explicitly pressing a logout button, a function installed in the MFP automatically performs logout after a predetermined timeout period, so that masquerade of a user can be reduced.
However, if another user operates the MFP before the automatic logout processing starts by timeout, the user can operate the MFP by masquerading. Further, the unauthorized user can steal confidential information of a high asset value.
As described above, the present MFPs cannot strictly manage a user authentication session and thus, for example, cannot conduct accurate charging in account management by counting the number of copied sheets, although the MFPs have a user authentication function. Further, when a confidential document is scanned, even a user who does not have a right to obtain the information can obtain the information by masquerading, which further causes a security problem that this action is recorded as another user's job in an operation log.
In order to solve the above-described problems, a user authentication session needs to be strictly managed. A session managing method is an example that is disclosed as countermeasures. This is a so-called network session management in which both sides communicating with each other constantly recognize each other while a WWW (world wide web) browser is communicating with a WWW server.
For example, Japanese Patent Laid-Open No. 11-212912 (corresponding to U.S. Pat. No. 6,587,880) discloses the following configuration: a browser provides information called a session identifier to a WWW server to access the WWW server, the WWW server requests verification of the session identifier to an identifier management server that manages the session identifier, and then the WWW server transmits a response to the browser based on the verification result.
According to Japanese Patent Laid-Open No. 11-212912, an authentication server manages a session identifier and the correctness of a network session is determined by adding the session identifier to information in a client-server communication. In this known technique, a server providing a service needs to transmit an inquiry to the authentication server every time the server wants to determine the correctness of a network session.
In this configuration of the known technique, the authentication server manages all network service sessions by centralized management. Therefore, the authentication server needs to control both authentication processing and session management, so that the performance thereof degrades when there are many nodes or many processing queues. Additionally, the authentication server needs to be changed when a service is newly added, which causes a scalability problem.